[youtube=XSFXzL4vCPg]

The following is a simulation for the above case.

/htdocs/ntnujava/ejsuser/2/users/ntnu/fkh/ballsFalling_pkg/ballsFalling.propertiesFull screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(998.6kB):double click downloaded file to run it. (3 times by 3 users) , Download EJS source View EJS source


Lagrangian's equation of motion L = T - U
[img]http://www.phy.ntnu.edu.tw/java/demoDrop/fig0.gif[/img]

with
[img]http://www.phy.ntnu.edu.tw/java/demoDrop/fig2.gif[/img]
and
[img]http://www.phy.ntnu.edu.tw/java/demoDrop/fig3.gif[/img]

We will get the following equations
[img]http://www.phy.ntnu.edu.tw/java/demoDrop/fig1.gif[/img]